Phonograph record disc

ABSTRACT

A synthetic resin moulded product has a moulded label equivalent portion having mirror-like smooth surface parts with a pattern and coarse surface parts in parts other than the pattern. The coarse surface parts have extremely small minute projections and depressions over the whole surface thereof, and also undulating uneven parts with another pattern. The label equivalent portion indicates the one pattern by a contrast of the lusterless parts formed by the coarse surface and the lustrous parts of the smooth surface, and at the same time indicates another pattern by the undulating uneven contour in the coarse surface. The manufacturing method forms the synthetic resin moulded product with the label equivalent portion.

States Patent [191 PHONOGRAPH- RECORD DISC Inventor: Susumu Genma, Tokyo, Japan Assignee: Victor Company of Japan, Ltd., Yokohama-city, Kanagawa-ken,

, Japan Filed: May 24, 1971 Appl. No.: 146,045

Foreign Application Priority Data May 25, 1970 Japan 45/44661,

US. Cl 16 1/116, 156/3, 156/14, 156/219, 161/42, 161/119, 161/413,

Int. Cl B32b 3/00 Field of Search 264/106, 107, 1, 220, 227, 264/284, 293; 156/62, 209, 219, 220, 3, 14; 161/2,.116, 42, 413, 119; 274/42, 9, 43,11, 44, 17

References Cited UNITED STATES PATENTS I 7/1920 Aylsworth 264/107 Jan. 22, 1974 2,697,893 12/1954 Schaum 161/2 2,337,703 12/1943 I 2,180,002 11/1939 Ford 161/2 Primary ExaminerWilliam A. Powell Attorney, Agent, or Firm-Louis Bernat [5 7 ABSTRACT A synthetic resin moulded product has a moulded label equivalent portion having mirror-like smooth urfa .PQEEQWJEDBJPEEEQfiBSl993 's ee part in parts other than the pattern. The coarse surface parts have extremely small minute projections and de pressions over the whole surface thereof, and also undulating uneven parts with another pattern. The label equivalent portion indicates the one pattern by a contrast of the lusterless parts formed by the coarse surface and the lustrous parts of the smooth surface, and

at the same time indicates another pattern by the undulating uneven contour in the coarse surface. The manufacturing method forms the synthetic resin moulded productwith the label equivalent portion.

3 Claims, 11 Drawing Figures Pmimin z 3. 787. 275

INVENTOR Susumu GENMF) I f BY I 4 v v AL x ATTORNEY PMENTEU 3,787. 275

INVENTOR SusuMu GENMH ATTORNEY PMENTEUJANZZIHH SL787. 2T5

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INVENTOR Susumu GENI IF) ATTORNEY I I PI-IONOGRAPII RECORD DISC This invention relates to a Synthetic resin moulded product and to a method of manufacturing the same and, more particularly, to a synthetic resin moulded product which is capable of indicating its contents by means of a label, without attaching of a separate label thereto. This method includes a moulding of the portion which is equivalent to the label, integrally with the product proper in a moulding process.

By way of example, the synthetic resin moulded product is hereinafter described with reference to a record disc. A conventional record disc is press-moulded in the following process. First, labels are prepared for both A-side and B-side, which labels are made of printed paper. Then, each label is mounted on stampers, with its umprinted side out, guided by a center pin of a press machine. Next, a required quantity of prehated and kneaded vinyl material is. charged between two stampers. The .two Stampers are pressed together to heat, press,.and cool the charged material, whereby a record disc is manufactured. These labels generally indicate the name of the music'recorded on the record disc, the names'o f its composers and its players, etc. The labels adher to the heated and melted material during the process of press-moulding, and they are stuck fast to the record disc when it has cooled and is taken out of the stampers.

However, the conventional method of manufacturing record discs using the labels of printed paper has the following disadvantages. (1 The labels are mounted on the press machine. This constitutes a great hindrance to making record disc with less man power and a shortening of a record disc manufacturing cycle. (2) The printing, drying, delivery etc. of labels require many process steps and a great deal of time, and the cost of a record disc increases by the cost of the lables. (3) In press-moulding of record discs, irregularity or breakage of labels frequently takes place. Also errors are sometimes committed by' an operatorin mounting labels on the press machine. These factors obstruct improvement of productivity in the record disc production. (4) In case of manufacturing reject,the record disc is crushed and regenerated as material. However, the labeled part is blanked and destroyed. The rest of the record disc is used for regeneration, because the label is stuck fast on the record disc and cannot be removed. The labeled part is thick and contains a large quantity of material. Accordingly, rate of regeneration of material is low due to the destroying of the labeled part.

In making a tape cartridge casing or a tape cassette casing, which has a label attached thereto, a similar operation of attaching the label to the casing is required with resulting disadvantages as described above.

It is, therefore, a general object of this invention to eliminate the aforementioned disadvantages and to provide a novel and useful synthetic resin moulded product which has obviated the necessity of attaching a label thereto, and a method of manufacturing the same.

Another object of the invention is to provide a synthetic resin moulded product in which the portion of the product equivalent to the label (hereinafter referred to as a label equivalent portion") is moulded integrally with the product proper, in the process of moulding the product, anda method of manufacturing the same. a

A further object of the invention is to provide a synthetic resin moulded product in which a predetermined pattern is made of a combination of lustrous parts and lusterless parts. The pattern is formed integrally with the surface of the product during the process of moulding the product, and amethod of manufacturing the same. The employment of this predetermined pattern as the label equivelent portion has obviated the necessity of using labels of printed paper or plastic sheet.

A still further object of the invention is to provide a moulded product having an integrally formed label equivalent portion in which a plurality of patterns are simultaneously provided, one being superposed upon another, and a method of manufacturing the same.

A still further object of the invention is to provide a synthetic resin moulded product which is capable of indicating its contents without attaching a separate label to the product, and a method of manufacturing the same. Accordingly, for this moulded product and the method of manufacturing the same (1) the operation of mounting separate labels on the press machine is not required and, the making of the moulded product without excessive man power and a shortening of the manufacturing cycle can be realized. (2) The printing, drying and delivery of the labels are not required, and the cost of the moulded product is reduced by the unit cost of the labels. Since the label equivalent portion is formed on a moulding die, there is a cost for making the die for forming the label equivalent portion on the die. This cost, however, scarcelyaffects the unit cost of the moulded product because a great number of the products are moulded by the same die. (3) There is no irregularity, breakage or error in mounting of the labels, which often takes place in the conventional products. This contributes to an improvement of good product ratio of the moulded product. (4) The label equivalent portion is made of the same material as the synthetic resin moulded product proper. Accordingly, when rejected moulded products are collected and regenerated, the entire moulded products can be regenerated as synthetic resin material and, therefore, the rate of regeneration of material is'remarkably improved.

Other objects and features of the invention will become apparent from the description made hereinbelow with reference to the accompanying drawings, i which:

FIG. I is a vertical sectional view of a lacquer master;

FIG. 2 is a vertical sectional view of a metal master;

FIG. 3 is a vertical sectional view showing a process in which a mother is obtained from the metal master shown in FIG. 2, according to one example of the method of manufacturing a synthetic resin moulded product embodying the present invention;

FIG. 4 is a vertical sectional view of the mother obthe predetermined pattern is exposed and developed;

FIG. 7 is an enlarged vertical sectional view of the mother shown in FIG. 6 after etching is effected thereon;

FIG. 8 is a vertical sectional view of the mother after etching;

FIG. 9 is a plan view of the label equivalent portion;

FIG. I is a vertical sectional view showing a state in which a stamper is obtained from the mother on which etching is effected as shown in FIG. 7; and

FIG. 11 is a vertical sectional view of a record disc moulded by the stamper.

Each embodiment of a method of manufacturing according to the invention will now be described in the order of the manufacturing process with reference to a record disc taken by way of an example of a synthetic resin moulded product.

First, sound grooves are formed by cutting on a lacquer disc. A silver mirror treatment is effected thereon to obtain a lacquer master having a sound groove portion 11. Preplating and electroforming are effected on the lacquer master 10 to obtain a metal master 12, as shown in FIG. 2, which has a sound groove portion 13. The metal master I2 is a preplated layer 14 and an electroformed plate 15. The above described process is conducted in a conventional manner.

Next, the separated surface of the metal master 12 is rinsed and, as shown in FIG. 3, a separating film I6 is provided on the separated surface. A mother preplated layer 17 having a thickness D is formed on the separating film 16 by preplating for a predetermined period of time. The label equivalent portion is located around a central aperture excluding a part corresponding to the sound groove portion of this preplated layer 17. There, a porous super thin film 18 is formed in a first predetermined pattern which is a reversed pattern of a pattern consisting, for example, of the figures of a dog and a phonograph. This first pattern may be formed by an electrically conductive super thin film or by forming projections and depressions by partially changing the electroforming speed on deactivated portions, instead of the porous super thin film as described above.

Electroforming is effected on the preplated layer 17 on which, as described above, the first pattern has been formed by small projections and depressions of the super thin film I8, whereby an electroformed plate 19 shown in FIG. 4 is formed. The preplated layer 17 and the electroformed plate 19 become a mother 20 which is to be separated at the separating film I6. It is to be noted that, in the electroforming of the plate 19, the crystal growth on the super thin film 18 is different from that on other flat part in a small hole of the film.

Consequently, the electroformed plate on the super thin film 18 grows in undulating wave-like projections and depressions which correspond to the projections and depressions of the super thin film 18. However, the growth is different depending upon the quantity of levelling agent used. The state of growth of the electroformed plate at a certain stage is indicated by thin lines 21a and 21!). It will be understood that the electroforming is actually made continuously, and the boundaries shown by the thin lines 2111 and 21b do not actually exist, but are here shown in the figure for convenience of explanation. As the electroformed plate grows, the above described undulating projections and depressions formed on the super thin film 18 are gradually levelled off, as shown by the thin lines 21a and 21b, due to a levelling effect, and the electroformed plate finally makes a uniform growth. The electroforming is uniformly grown at a part having no super thin film 18.

The mother 20 consists of the preplated layer 17, the super thin film 18, and the electroformed plate 19. The mother is separated at the separating film 16 from the metal master 12. The separated surface is rinsed, and

masked with an acid-proof lacquer 23 on the surface of the mother 20, leaving the label equivalent portion 22, as shown in FIG. 5.

After masking with the acid-proof lacquer photoresist is' coated on the label equivalent portion 22. The photo-resist is exposed to light, through a second predetermined pattern including letters etc., and then is developed. As a result, the photo-resist 25 remains in the exposed parts as shown in FIG. 6. In the pattern part 24, excluding parts of the remaining photo-resist 25, the surface of the preplated layer 17 of the mother 20 is exposed.

The mother 20 is soaked in an etching acid. The photo-resist 25 and the acid-proof lacquer 23, except on the second pattern part 24, prevents an attack of an etching solution such as a ferric chroride solution or a mixed solution of nitric acid and acetic acid. The aforementioned etching solution may be sprayed over the mother 20. The mother 20 having the second pattern part 24 is eaten away by the etching solution to the depth D as shown in FIG. 7. The depth D is selected to be greater than the thickness D of the preplated layer 17. Accordingly, the etching is effected through the preplated layer 17 and the upper portion of the electroformed plate 19. The remaining photo-resist 25 and the acid-proof lacquer 23 are removed to obtain a mother 28 shown in FIG. 8 which has etched coarse surfaces 26 and smooth surfaces 27, on its label equivalent portion.

The etched coarse surfaces 26 of the electroformed plate 19, made by the above described etching process, are formed in surfaces having very minute and fine projections and depressions, due to the melting out of extremely fine minute crystal grains of the electroformed plate 19. These etching surfaces are undulatory because they are etched in accordance with the undulating contour formed during the growth of the electroformed plate 19. This pattern of the undulating contour is a reversed pattern of the aforementioned pattern on the super thin film 18. The above described coarse surfaces are superposed upon this undulating contour.

In this embodiment, the depth of the extremely fine minute projections and depressions of the above described coarse surface is about Su, and the width is about l0p.. The depth is preferable in a range of l5 and the width in a range of 515p.. The average wave figure of the undulating contour is in the order of several hundred microns.

The coarse surface parts have a satin-like surface and appear somewhat whitish, due to an irregular reflection of light. Whereas, the undulating pattern appears in moderately undulating contour on the satin-like surfaces with a much greater interval between the crests of the waves, than the interval between the projections of the coarse surface. The smooth surface parts 27 correspond to the second pattern consisting of the letters etc, whereas the coarse surfaces 26 correspond to the parts excluding the second pattern.

Consequently, in the label equivalent portion 29, there appears, as shown in FIG. 9, a first pattern 39 consisting, for example, of the figures of the dog and a phonograph on the satin-like surfaces of the coarse surface parts. Again, a second pattern 40 consisting, for example, of the letters VICTOR" formed by the above described second pattern stands out in relief with a mirror-like luster on the ground of the satin-like coarse surfaces.

As shown in FIG. a separating film 30 is formed on the surface of the mother 28. Then, electroforming is'used to form an electroformed plate 31. The electroformed plate 31 is separated at the separating film 30 from the mother 28. Thus, a stamper 33 is formed having a label equivalent portion 32 which includes a reversed pattern of the pattern formed on the label equivalent portion 29 of the mother 28.

By the foregoing processes, an A-side stamper 33a and a B-side stamper 33b are formed, as shown in FIG. 11. These stampers 33a and 33b are mounted on a press which may be of any conventional type. A required quantity of synthetic resin material which has been preheated and kneaded is charged and pressmoulded between the two stampers 33a and 33b. Thus, a record disc 35 is made of synthetic resin material 34. The record disc'35 is moulded on both sides with label equivalent portions 38a and 38b being formed by the label equivalent portions 320 and 32b of the stampers 33a and 33b. The label equivalent portions 38a and 38b includes coarse surface parts 36a and 36b having undulating parts upon which extremely fine minute projections and depressions are superposed and smooth surface parts 37a and 37b.

In the coarse surface parts 36a and 36b of the record disc 35, the coarse surface parts appear somewhat whitish, due to irregular reflection of light. The first pattern includes figures of the dog and phonograph, formed by its undulating contour. The smooth surfaces 37a and 37b have mirror-like luster. The second pattern, including the letters VICTOR, stands out in relief on the lusterless, satin-like coarse surface parts.

in this embodiment, the etching treatment for forming the coarse surface parts is effected on the mother. However, the etching treatment for forming the coarse surface parts may, also, be effected on the metal master or the stamper.

In the embodiment described above, the figures are formed by a first pattern formed by superposing the coarse surface parts upon the undulating surface parts, and the letters are formed by a second pattern formed on the smooth surface parts. This arrangement, however, may be reversed. Namely, the first pattern may be used forletters, and the second pattern may be used for figures.

Further, in the foregoing embodiment, the undulating contour parts having the coarse surfaces are formed in the depressed portions, and the smooth surface parts are formed on the top surfaces of the portions projecting above these depressed portions. It is also possible to reverse this arrangement. Namely, the undulating contour parts may be formed on the top surfaces of the portions projecting above the depressed portions, and the smooth surface parts may be formed in the depressed portions. This reversed arrangement is achieved by effecting the above described etching on the metal master.

The foregoing embodiment has been explained with reference to a record disc, which were taken by way of an example of the synthetic resin moulded product. This invention, however, is .not limited to this record, but it is applicable to a tape cartridge casing, a tape cassette casing and any other synthetic resin moulded products, which have heretofore required the operation of attaching a separate label thereto.

This invention is not limited to these embodiments. Variations and modifications may be without departing from the scope and spirit of the invention.

What I claim is: Y

l. A synthetic resin moulded phonograph record disc having a label equivalent portion formed integrally therewith during a moulding process and formed in a part other. than the sound grooves of said phonograph record disc, said label equivalent portion comprising coarse surface parts having a surface with minute projections and depressions thereon, smooth light reflecting surface parts having smooth surfaces, said smooth surface parts forming. a predetermined pattern against a background of said coarse surface parts, the depth of the projections and depressions in said coarse surface parts being in a range of 1-5 H and the width thereof in a range of 5-l5 u, and uneven parts formed on said coarse surface parts with another pattern having projections and depressions which are much larger than the projections and depressions of said coarse surface parts, said coarse surface parts being lusterless due to the irregular reflection of light therefrom and said smooth surface parts having a luster of mirror-like reflectivity whereby the predetermined pattern is recognized by the contrast between the lusterless coarse sur face parts and the lustrous smooth surface parts.

' 2. The synthetic resin moulded phonograph record disc as defined in claim 1 wherein said predetermined pattern indicates letters and said other pattern indicates figures.

3. The synthetic resin moulded phonograph record disc as defined in claim 1 wherein said label equivalent portion further comprises depressed parts which are below the level of said smooth surface parts, saidcoarse surface parts and said uneven parts being formed on the bottom surface of said depressed parts. 

1. A synthetic resin moulded phonograph record disc having a label equivalent portion formed integrally therewith during a moulding process and formed in a part other than the sound grooves of said phonograph record disc, said label equivalent portion comprising coarse surface parts having a surface with minute projections and depressions thereon, smooth light reflecting surface parts having smooth surfaces, said smooth surface parts forming a predetermined pattern against a background of said coarse surface parts, the depth of the projections and depressions in said coarse surface parts being in a range of 1-5 Mu and the width thereof in a range of 5-15 Mu , and uneven parts formed on said coarse surface parts with another pattern having projections and depressions which are much larger than the projections and depressions of said coarse surface parts, said coarse surface parts being lusterless due to the irregular reflection of light theRefrom and said smooth surface parts having a luster of mirror-like reflectivity whereby the predetermined pattern is recognized by the contrast between the lusterless coarse surface parts and the lustrous smooth surface parts.
 2. The synthetic resin moulded phonograph record disc as defined in claim 1 wherein said predetermined pattern indicates letters and said other pattern indicates figures.
 3. The synthetic resin moulded phonograph record disc as defined in claim 1 wherein said label equivalent portion further comprises depressed parts which are below the level of said smooth surface parts, said coarse surface parts and said uneven parts being formed on the bottom surface of said depressed parts. 